Phosphinoborine compounds and their preparation



tates This invention relates in general to the preparation of phosphinoborine polymers, the boron atoms of which are halogenated, and more particularly to the preparation of B-halogenated phosphinoborine polymers by the treatment with a halogenating agent of a preformed phosphinoborine compound in such a fashion that B-halo phosphinoborine compounds are formed of a structure predetermined by the nature of the substituents present on the phosphorus and boron moieties before halogenation.

Phosphinoborines, compounds which are polymeric in nature and which are composed of a number of units joined one to the next, each of the units being composed of a phosphorus atom joined to an adjacent boron atom, are described in abandoned application Serial No. 446,147 filed July 27, 1954, by Anton B. Burg and Ross I. Wagner, for Phosphinoborine Compounds and Their Preparation. As set forth here and in the various co-pending continuation-in-part applications filed subsequent to the aforementioned application, these phosphinoborine compounds are of value as high temperature dielectric materials. The phosphinoborine compounds having one or more halogen groups bonded to the boron atom are in certain respects superior to the basic phosphinoborine compounds having no halogens bonded to the boron. That is, they are superior in certain applications. They have someatent fiice what higher melting points and greater oxidative stability than the corresponding non-halogenated phosphino-borines, and thus may be used in applications where only the most high melting of the phosphinoborine materials may be employed, i.e., one such application is as a dielectric material where extremely high temperatures and opportunities for chemical reaction are encountered. However, the preparative methods available for the manufacture of the B-halogenated phosphinoborine compounds are in certain respects more diliicult than the preparative methods available for the manufacture of the corresponding non-B-halogenated phosphinoborine compounds.

It is therefore an object of this invention to provide for the preparation of B-halogenated phosphinoborine compounds, the halogen substituents of which may or may not be mixed.

Another object of the invention is to provide for the preparation of phosphinoborines, the B atoms of which may be bonded to halogen atoms.

A further object of this invention is to provide a method for the production of B-halogenated phosphinoborine compounds which involves the treatment of a preformed phosphinoborine compound with a halogenating agent.

Still another object of this invention is to provide a 'halogenating method for use with phosphinoborine compounds, which method does not affect the polymeric nature of the phosphinoborine compound treated; that is, where a compound treated is initially a linear polymer it will remain such and where a compound is initially a cyclic polymer it will continue to be a cyclic polymer following treatment with the halogenating agent and will exhibit the general properties common to cyclic phosphinoborine polymers.

Broadly, it has been found that phosphinoborines which have been preformed either as linear or cyclic polymers Patented Mar. 13, 1962 may be treated thereafter with certain halogenating agents whereby to convert the phosphinoborine analog. A phosphinoborine may be prepared from the appropriate phosphine borine by pyrolysis and the phosphinoborine treated with the appropriate halogenating agent. Such halogenating agents are the free halogens, hydrohalogen acids and reactive halogenated hydrocarbons in which the halogen is bonded to a saturated carbon atom. The halogenated hydrocarbons may be used alone or together with a catalyst such as an aluminum halide.

More particularly, a process has been developed which is suitable for the preparation of B-halogenated phosphinoborines which involves the use of preformed phosphinoborines of the type [RRPBHR] where R and R represent hydrocarbon substituents and R" represents either hydrogen or a hydrocarbon substituent. These preformed phosphinoborines thereafter are treated with a halogenating agent such as a free halogen, a hydrohalogen acid or a reactive halogenated aliphatic hydrocarbon in which the halogen is bonded to a saturated carbon atom. Commercially available reactive halogenated hydrocarbons are the halogenated methanes, monohalo-substituted hydrocarbons having from 2-8 carbon atoms (compounds of the type C H X where 12:1-6) chlorinated and brominated C compounds and (CH Br A particularly effective representative of the group C H ,,X is C Cl In short, any of the hydrocarbon materials commonly used as halogenating agents may serve.

One phase of this process involves the halogenation of a phosphinoborine of the general formula [RRPBI-IR] with a halogenated material of the general formula CYYY"X wherein X represents a halogen and the symbols are either hydrogen or halogen or together represent a lower alkyl radical. Such materials are generally referred to as halogenated hydrocarbons (and are so designated hereinafter), even though, as is thecase' with carbon tetrachloride, all hydrogens of the original hydrocarbon have been replaced with halogen atoms. Preferably, aluminum halides are used as catalysts. However, a catalyst is not essential. The halogen present in the catalyst should correspond to the halogen of the halogenating agent. That is, the halogen should correspond provided it is not desired to obtain a phosphinoborine having mixed halogens bonded to the boron. The utilization ofthe process wherein mixed halogens are present whereby to produce a phosphinoborine which has mixed halogen atoms is set forth in Example X below; Ithas been found that the use of aluminum chloride alone as a catalyst is not a satisfactory way to produce the halogenated phosphinoborine. An effort to substitute chlorine in a dimethylphosphinoborine trimer using AlCl in the absence of an alkyl halide resulted only in the degradation of the phosphinoborine and the benzene solvent.

The reaction is carried out at a temperature of-0-200 C. and preferably from 20-l50 C. The lower portion of the preferred temperature range is suitable when a catalyst is used and the higher temperatures are required without a catalyst. The reaction is carried out in the presence of a solvent and the halogenated hydrocarbon used generally serves this purpose as well. Under certain circumstances hydrocarbon solvents such as benzene or petroleum ether may also be used.

Examples of this phase of the process are set forth below by way of illustration.

EXAMPLE I A solution of 13.7 g. (0.0618 mole) [(CH PBH;,] in 137.3 g. (0.892 mole) CCl was sealed in a Pyrex tube under vacuum. The tube was heated at C. for 113 hours during which time a crystalline precipitate formed. The tube was cooled and opened and the solvent was distilled into a tared weighing tube. The recovered solvent mixture weighed 124.8 g. indicating that 5.86 gram-atoms of chlorine (97.6 percent) had exchanged with hydrogen per mole 'of dimethylphosphinoborine trimer. The product, [(CH PBCl melted at 377-8 C.

EXAMPLE II A 0.0468 g. (0.135 mmole) sample of the simplest dimethylphosphinoborine methylphosphinoborine copolymer, [(CH PBH CH PBH, and 1.2036 g. (7.824 mole) CCL; were heated in a scaled tube at 140 C. for 17 hours. The tube was cooled and opened. The solvent was recovered and weighed 1.1658 g. From the Weight loss the product was determined to be Details with respect to the structure of the copolymer described herein may be found in our co-pending application Serial No. 680,625, filed August 27, 1957.

EXAMPLE III A 0.5196 g. (1.97 mmoles) sample of and 11.7762 g. (76.55 mmoles) CCl were sealed in a tube and heated at 120 C. for 14.5 hours. The tube was cooled and opened and the loss in weight of the solvent was determined to be 0.2878 g. From the loss in weight the average number of chlorine atoms per mole of methylethylphosphinoborine trimer was found to be 4.25. The partially chlorinated material was rescaled in a tube with 7.6852 g. (5.00 moles) of fresh CCl and heated at 130 C. for an additional 25 hours. An additional weight loss of (0.0510 g.) was sufficient to raise the average number of chlorine atoms per mole of [CH (C I-I PBH to 4.99. The final product,

[CH (C H )PBCl CH (C I-I PBHCl was a low melting waxy solid.

EXAMPLE IV A solution of 0.0530 g. (0.179 mmole) [(CH PBH in 2.9020 g. CHCI was sealed in a heavy-wall Pyrex tube under vacuum. The tube was heated for 76.5 hours at 135 C. On cooling the tube to 25 C. a crystalline precipitate was observed floating in the solution. The cooled tube was opened and the solvent was distilled into a tared tube. From the weight loss of the solvent an average of 4.68 gram-atoms of chlorine per mole of [(CH PHB had been introduced. The solvent was returned to the tube containing the partially chlorinated dimethylphosphinoborine tetramer. The tube was rescaled and heated for an additional 383 hours. The solvent was again removed and found to weigh 2.8668 g. Approximately 0.3 cc. of CH; had also been formed. From the loss in weight of the solvent and the CH produced, an average of 5.8 gram-atoms of chlorine per mole of had been introduced. A sample of the product after recrystallization from chloroform had a melting point of 320323 C. and analyzed 33.2 percent Cl corresponding to 4.08 gram-atoms chlorine per mole of [(CH PBH EXAMPLE V A 0.2135 g. (0.9633 mmole) sample of [(CH PBH was sealed in a Pyrex tube with 0.0605 g. (0.454 mmole) AlCl and 3.0936 g. (20.110 mmole) CCl The tube was heated in a refluxing bath of CCL; for 1.25 hours during which time a crystalline precipitate formed. The cooled tube was opened and the solvent was distilled into a tared weighing tube. The recovered solvent Weighed 2.8942 g. indicating that 6.01 gram-atoms of chlorine had exchanged with hydrogen per mole of dimethylphosphinoborine trimer. The [(CH PBCl after washing three times with water to remove AlCl melted at 376-7" C.

EXAMPLE VI A 0.0877 g. (0.300 mmole) sample of [(CH PBH and 0.1820 g. (1.365 mmoles) AlCl were sealed in a Pyrex tube with an excess of CH CI (4 ml.) which served as a solvent for the reaction mixture as well as a reactant. The reaction was allowed to proceed for 135 hours at 25 C. and yielded 40.7 cc. CH indicating that 6.12 gram-atoms chlorine per mole [(CH PBH had been exchanged for hydridic hydrogen. The tube was rescaled and heated to C. for 4 /2 days in an autoclave producing an additional 4.4 cc. CH Based on the volume of CH; produced, 6.78 gram-atoms chlorine per mole of [(CH PBH had exchanged.

EXAMPLE VII A 0.3248 g. (1.465 mmoles) sample of [(CH PBH and 0.7245 g. (1.777 mmoles) A11 were sealed in a Pyrex tube with an excess of CH I (3 ml.) which served as a solvent for the reaction mixture as well as a reactant. The mixture was heated at 50 C. for 55 hours producing 194.3 cc. CH (98.6 percent yield). The CH I was distilled from the tube under vacuum. The resulting solids were treated with a sufiicient quantity of CH I to dissolve the product from which All was removed by washing three times with water. On evaporating to dryness the organic layer yielded 1.3564 g. (1.388 mmoles) [(CH PBI The dimethylphosphinodiio doborine trimer decomposed rapidly above 400 C. without preliminary melting.

EXAMPLE VIII A 0.2394 g. (1.080 mmoles) sample of [(CH PBH and 0.3690 g. AlBr (1.485 mmoles) were sealed in a Pyrex tube with an excess of CH Br (3 ml.) which served as a solvent for the reaction mixture as well as a reagent.- The mixture after standing 15 hours at 25 C. had produced 141.2 cc. CH (97.3 percent yield). The CH Br was distilled from the tube under vacuum. The resulting solids were treated with a suflicient quantity of CHBr to dissolve the product from which AlBr was removed by washing three times with water. On evaporating to dryness the organic layer yielded 0.7369 g. (1.060 mmoles) [(CH PBBr The dimethylphosphinodibromoborine timer decomposed rapidly above 400 C. without preliminary melting.

EXAMPLE IX A 0.2544 g. (1.148 mmoles) sample of [(CH PBH and 0.1830 g. AlCl (1.372 mmoles) were sealed in a Pyrex tube with an excess of CH Cl (3 ml.) which served as a solvent for the reaction as well as a reagent. The mixture after standing for 12 hours at 25 C. had produced 149.8 cc. OH; (97.1 percent yield). The CH Cl was distilled from the tube under vacuum. The resulting solids were treated with a sufficient quantity of CHCl to dissolve the product from which AlCl was removed by washing three times with water. On evaporating to dryness the organic layer yielded 0.4875 g. (1.138 mmoles) [(CH PBCI melting at 377-8 C.

EXAMPLE x In a preparation similar to that set forth in Example VI above, 0.1879 g. (1.409 mmoles) aluminum chloride was used as the catalyst, 3 ml. methyl bromide as the halogenating agent and solvent for 0.2794 g. (1.261 mmoles) dimethylphosphinoborine trimer. The reaction products were methane and 0.6830 g. of a halogenated material having the empirical composition EXAMPLE XI Into an 80 ml. glass bomb tube containing 0.3558 g.

(4.82 mmoles as monomer) of dimethylphosphinoborine linear polymer and 0.70 g. (5.2 mmoles) of aluminum chloride was condensed about 6 ml. of methyl chloride. The tube was sealed and allowed to stand at room temalkyl halides and acetic acid. This reaction proceeds readily at room temperature and generally requires a re action time of only a few minutes. Permissible reaction temperatures are found within the range of -50 to 200 perature for 18 hours. The tube was opened and 213.6 5' C. depending on the halogen employed. Chlorine may cc. (98.9%) of methane was collected. The excess methbe used at the lower of the temperatures, bromine at yl chloride was removed and the yellow contents of the somewhat higher temperatures and iodine at the highest tube were extracted with boiling chloroform but only an temperatures. estimated 0.03 g. of material was extracted. The insol- Various examples illustrative of this phase of the procuble product was next washed with boiling water, 4-10 ess are set forth below. ml. portions of 4 N hydrochloric acid, 310 ml. portions of distilled Water and 310 ml. portions of methanol, EXAMPLE XXII I leaving 0.5396 g. (78.6%) of a colorless product, M.P. A 25 aliquot of 01255 N a Solution (3133 above 360 C., which analyzed: C, 18.00; H, 5.02; CI, mmoles) in bromobenzene was added to 0.0550 g. (0.248 4524; Calc. for c 11 PBc1 c, 18.82; H, 4.23; c1, 49.66. g o e) C M Z? g i111. b z

enzene. n excess 0 aqueous 0 so utlon EXAMPLE XII ml.) and 2 g. NaHCO were added to the mixture imme- A 0.2437 g. (1.099 mmoles) quantity of diately. A total of 16.35 ml. of 0.1000 N As O was required to titrate the liberated iodine. Thus, 1.505 (113) 2PBH213 m./eq. Br were used up or 3.03 gram-atoms bromine was 1sealedAlinla urge together with 0.4205 g. (3.11534 wer int duced per l f (CH PBH mmo es) C 3 an 4 ml. n-C H C. As the tu e warmed to room temperature a vigorous gas evolution was EXAMPLE XXIII observed and the mixture turned to a gummy orange- Two separately weighed samples of [(CH PBH colored mass. After standing for 4 days without further were each dissolved in 5 ml. of CH Br 25 ml. of a change, the tube was opened, and the volatile materials solution of bromine in CH Br was added to each soluwere removed and analyzed by infrared and vapor chrotion of the trimer. After 10 minutes, the addition of pomatographic techniques with the following results: 2.84 tassium iodide gave no indication of excess bromine. cc. H 323 cc. I-ICl, 215 cc. n-C H 34.4 cc. i-C H and Both samples were washed with Water and evaporated to the solvent which now contained 58.5% n-C H Ci, 35.9% dryness. Recrystallization of sample A (see Table 2) s-C H Cl, and lesser amounts of C and C chlorides. from methanol-water yielded colorless needles, M.P. From the residue, which was dissolved in CHCl and l27129 C. The compound was analyzed for carbon washed with dilute HCl, was isolated a 0.8138 g. mixture and hydrogen and its molecular weight was determined of an orange oil and colorless solid. The solid isopiestically with the following results: C, 18.25%; H, 5.74%; M, 359; calc. for (CH P B I-I Br C, 18.99%;

[(CH3)2PBC12]3 H, 5.84%; M, 379.46. having a M.P. of 378-385 C. was isolated in 91.4% yield bl 2 (0.4301 g.).

EXAMPLE Wt. Wt. Perce t A mixt re or 1 4 (4 3 mm l 3)2 2]3. 3515 43333 145 $5333 T3151... 2.85 g. (21.4 mmoles) AlC1 and 110 ml. CCl was refluxed for 1 hour. The temperature dropped from 76 C. A 8 2? 7389 9 2579 0 9935 32 74 1 9 4 to 72 C. durin the first 10 minutes. The cooled mixa A s ture was Washed with 12 N HCl and three times with 5 M919 26'95 04389 92579 08124 2061 Water. The CCL solution was evaporated to dryness and the 19.4 g. (100%) residue was recrystallized from chloro- EXAMPLE XXIV form. The density of the product, [(CH PBCl was A solution containing 1.9840 g. (12.41 mmoles) of determined, d =1.44. bromine in 2 ml. of methylene bromide was added in 3 Details regarding additional runs which may be made minutes to 0.9155 g. (4.130 mmoles) of dimethylphosusing other phosphinoborines and various typical catalysts phinoborine trimer dissolved in 15 ml. of methylene broand halogenating agents are set out in tabular form below. mide at room temperature. The solution became hot and Table 1 Phosphinoborine AlXa Halogenated Hydrocarbon Halogenated Phosphino- Example Phosphinoborine borine Product Grams mmoles X Grams mmoles Com- Grams mmoles pound n-o rnn rnrrzh 0.7041 1.262 I 0.462 1.134 GHQIE 1.1461 4.2785 [(C5H1Q3PBI213 n-CgHflC HQPBI-Izh.. 0.671 1.928 Br 0. 252 0.946 omen 1.820 19.164 [Il-C3H7(C2H5)PBBI2]5 ho mhPBHzh 1.337 4.370 01 0.248 1.864 001. 1.605 10.431 [(OflnhPBonp n-0.H3)2PBH2]4.. 6.238 13.161 Br 1.798 6. 741 01113113 1.725 34.352 (n-(hHaJzPBBrsla n-o muOHayPBHfl 2. 375 3. 472 01 0.349 2. 623 0014 3.041 19.766 n-owumounrnonh [CH3(i-O3H7)PBH2]3.. 1.070 3. 526 01 0. 332 2. 492 0014 2.140 13. 913 [CHa(i-C4H7)PBC1; ]9 [(GtH hPBHfla 4. 997 7.931 01 1.149 8.621 0142012 6.1285 72.151 o HHpPBonh [CHflGHmlfBHzh 7. 929 26.431 01 0.365 2. 741 001. 1.3169 8.902 [([3l-I(OHz)aI|BOl2]a The second of the alternative methods for halogenating hydrogen bromide was evolved. The solvent was removed an already formed phosphinoborine involves the treatment under vacuum and the yellow residue was recrystallized with a free halogen of a phosphinoborine of the type from a 10:1 methanol-Water mixture giving 1.099 g. of [RRPBHR"] Where n is an integer indicative of the colorless material, M.P. 133-142 C. (corr.). A second degree of polymerization and where R and R are hydrocrop of 0.477 g. of colorless crystals, M.P. 109 C. carbon radicals and R" is either hydrogen or a hydrocar- (corr.) was also obtained. The first crop was recrystallized bon radical. Preferably the halogen is dissolved in a corfrom a 1:1 cyclohexane-Skelly F mixture giving crysresponding liquid halogenated hydrocarbon. Preferred tals having M.P. 164 C. (corr.) analyzing Br, 55.6. solvents are the halogenated benzene compounds, liquid 75 (Calc. for C H P B Br Br, 52.3). A total of 1.659 g.

(86.9%) of material assumed to be tribromide was obtained.

additional runs which may be made using free halogen in the B-halogenation process.

Table 3 Phosphlnoborine Halogen Added Example Phosphinoborine Solvent Halogen Halogcnated Phosphinoborine Product Grams mmoles Grams mmoles [CZHMCHZOPBHJIS 0.1507 0. 5708 CHQBI2 3. 426 [C2H5(CI'I3)PBBI2]3 [CH3 (i-C3I-I7) PBH 0.0827 1. 631 [CI-13(i- Cal'h) PB C1213 [n-C ,H15(CH3) PBII 5. 251 n- 01111563113) PBI'IIJQ [n C QHMCHQPBH 1. 844 CrzHMCHQPB C12]; [(CsHnMPBHfla 1.473 (CQHIQZPBHCHQ [(OtHmPBHz]. 6. 548 (CGHmPBBnh (D GHzOuHOz B112]; 0. 2060 CHzBIr 1. 228 (D-CH3C5H4)1PBBI3]3 CH2(CH:)3PBH2]3 0. 9580 CH3COOH 2. 894 [CH2(CH2)3PBHBI]3 XXXVII 115) :PBHzh 0.1022 0. 33 OHBrs Br: 0. 3302 2. 066 [(021 21 Blink EXAMPLE XXV To a stirred ice cold solution of 1.4897 g. (6.720 mmoles) of dimethylphosphinoborine trimer in 35 ml. ether was added in 5 minutes 3.2219 g. (20.16 mmoles) of bromine. After being stirred for 35 minutes at room temperature, the solvent and hydrogen bromide was removed from the yellow solution under vacuum. The colorless residue was recrystallized as in Example XXIV. The first crop of crystals from methanol-water weighed 1.735 g. (55.7%) and had M.P. 110-l16 C. (corr.). Recrystallization from cyclohexane-Skelly F gave crystals, M.P. 119-126" C. (corr.) analyzing: Br, 53.4. (Calc. for CQH21P3B3BI'3, B1,

EXAMPLE XXVI To a solution of 0.9233 g. (4.165 mmoles) of dimethylphosphinoborine trimer in 25 ml. glacial acetic acid was added in 10 minutes 4.765 ml. (12.499 mmoles) of 2.623 M bromine in acetic acid solution. The reaction temperature was :5" C. Immediately after bromine addition was completed, 50 ml. of water was added to the reaction mixture and the resulting precipitate was isolated by filtration. The product was recrystallized from absolute methanol. The first crop of crystals weighing 1.197 g. (62.7%) had M.P. 113-120 C. (corr.), and analyzed: C, 15.97; H, 4.79; P, 18.68; B, 7.25; Br, 52.22. (Calc. for C H P B Br C, H, P, B, 7.08; Br, 52.30.) A total of 1.523 g. (79.8%) of purified tribromide was obtained.

EXAMPLE XXVII Following the procedure of Example XXVI, 20.1433 g. (0.09084 mole) of dimethylphosphinoborine trimer in 550 ml. of glacial acetic acid was treated with 43.6 g. (0.273 mole) of bromine in 85 ml. of acetic acid. A total of 31.16 g. (74.8%) of tribromide, M.P. 109- 115 C. (corr.) was obtained after recrystallization from absolute methanol analyzing: C, 15.64; H, 4.72; P, 20.2; B, 7.08; Br, 52.19. (Calc. for C H P B Br C, 15.72; H, 4.74; P, 20.28; B, 7.08; Br, 52.30.) Second and third crops of tribromide brought the total isolated yield to 38.1 g. (91.5%) although the last crops had lower melting points than the first.

EXAMPLE XXVIII Following the procedure of Example XXVI, 9.240 ml. (24.24 mmoles) of 2.623 M bromine in glacial acetic acid was added to 0.8961 g. (4.042 mmoles) of dimethylphosphinoborine trimer in 25 ml. of glacial acetic acid. Recrystallization of the product from methanol and methanol-benzene mixtures gave four different fractions which ranged in melting point from l26207 C., none of which analyzed for the hexabromide and probably are mixtures of tri, tetra, penta and hexabromides. An infrared spectrum of the highest melting fraction, which analyzed: C, 13.82; H, 4.12; Br, 59.00, was obtained for reference.

The table below sets forth reactants and quantities for The third alternative by means of which phosphinoborines of the type [RRPBHR] may be converted to B-halogenated phosphinoborines involves the treatment of such phosphinoborines with a hydrohalogen acid in either the liquid or gaseous state. No solvent is needed in the practice of this method and, because of the exothermic nature of the reaction, it is preferred to cool the phosphinoborine into which the hydrohalogen acid is run to a sufiicient degree that the mixture may be warmed to initiate the reaction. Ready methods of suitably cooling the reaction vessel containing the phosphinoborine are by means of a Dry Ice bath or liquid nitrogen.

Lower temperatures slow the reaction somewhat While it becomes progressively more rapid as the temperature is allowed to increase. The permissible temperature range may be set out as C. to +25 C. for liquid hydrohalogen acids and as 25 C. to 300 C. for gaseous acids.

EXAMPLE XXXVIII A 0.1236 g. (0.5576 mmole) sample of [(CH PBI-l was added to a large excess (251111.) of anhydrous HP at 60 C. in a polyethylene bottle. An immediate evolution of H was observed. The HP was distilled from the product, [(CI-I PBF which was then washed with water. The product melted at l278 C.

EXAMPLE XXXIX A 0.0955 g. (0.431 mmole) sample of [(CH PBH was placed in a stainless steel cylinder which was then cooled to 196 C. and evacuated. Approximately 18 ml. of liquid anhydrous hydrogen chloride was condensed into the cylinder which was allowed to stand at 25 C. for 89 hours. After cooling to -196 C., 13.6 cc. H was removed from the cylinder. An additional 121 hours at 25 C. yielded another 2.5 col-l The HCl was allowed to escape from the cylinder and the residue was extracted with four 3 ml. portions of methanol. The extract was evaporated to dryness. The product was isolated by sublimation at C. under high vacuum from the solid chlorides of iron, chromium, and nickel which had also been formed. A total weight of 0.1001 g. of product analyzing 18.3% chlorine was obtained. Thus under these conditions 1.20 gram-atoms chlorine per mole of [(CH PBH have been introduced in place of hydridic hydrogen.

EXAMPLE XL A 0.0146 g. (0.0659 mmole) sample of [(CH PBH was sealed in a Pyrex tube with 47.6 cc. of anhydrous HCl. The tube was heated for 43 hours at 300 C., during which time 2.30 cc. H were produced (26.0% of theoretical). The product was inhomogeneous and melted at 70 C.

Details relating to various additional typical runs which are possible are set out below in Table 4; in each case the halogenation of a phosphinoborine by use of a hydrohalogen acid is shown.

Table 4 Phosphinoborine Anhydrous HX Halogenated Phosphinobo- Example Phosphinoborine time Product Grams mmoles X 1111.

I XLI [CzH(CH3)PBH2]3 0.0525 0.3124 F [C2H5(OH3)PBF XLII [H-C12H25(OH3)PBHz]3 0.2613 0.3820 F 30 [H-C12H25(CI-I3)PBF;]3 XLIII [(CGH5)ZPBHB]B 0.0806 0.1357 F 15 [(COH5)2PBF2]3 XLIV l(D-CHsCeH4)2PBHz]3 0.1634 0.2410 F 25 [(D-CHaCaHOzPBFzh XL [CH2(CHz)aPBH2]3 0.3362 1.1209 F [CH2(CH2)3PBF2]3 XLVI [(OzHshPBHz]: 0.1175 0.3841 B1 [(C2H5)2P]3B3 6Bl In each case (excepting where HF is used) the phos- 15 We claim:

phinoborine reactant should be placed in an evacuated stainless steel cylinder and the phosphinoborine cooled in liquid nitrogen to about 196 C. In those cases where HF acid is used, a polyethylene bottle preferably serves as a reaction vessel.

In each case, after the addition of the appropriate acid, the mixture is allowed to warm sufficiently to initiate the reaction.

The B-halogenated compounds to which this invention is directed are new compositions of matter. Most of them are phosphinoborine polymers of ring configuration composed of between three and four phosphinoborine units, preferably three units, individual monomers of which have the formulae RRPBYY' and wherein the symbols R and R are alkyl, lower alkenyl, lower cycloalkyl, phenyl, lower alkyl-substituted phenyl, and wherein Y and Y are either hydrogen or halogen, at least one of Y and Y representing a halogen, and m is an integer of between 1 and 6. For a discussion of the structures of analogous trimers and tetramers, see application Serial No. 666,213, filed June 17, 1957 for Phosphinoborine Compounds and Their Preparation now Patent No. 2,925,440.

Alternatively, the monomers aforementioned may form linear chains through tetracoordinate boron-to-phosphorus bonding. See co-pending application Serial No. 678,429 filed August 15, 1957, and now abandoned for a discussion of analogous polymers. The new compositions of matter have the general formula (RRPBYY') where n is an integer greater than 4 and less than 1000. Similarly, the halogenated co-polymers of the general formula [RR'PBYY] [R"PBH] (eg. Example II) are new compositions of matter. For details of the structure of the type polymers formed, see application Serial No. 680,625 filed August 27, 1957, for Phosphinoborine Compounds and Their Preparation. In each instance, the co-pending application referred to discloses polymers which are identical to those claimed here except that one or more hydrocarbons moieties or hydrogens of the compounds disclosed earlier are replaced with halogen here.

Obviously, many modifications and variations of the invention as hereinbefore set forth may be made without departing from the spirit and scope thereof, and therefore only such limitations should be imposed as are indicated in the appended claims.

This application is a continuation-in-part of application Serial No. 678,428 filed August 15, 1957 for Linear B-Halogenated Phosphinoborines and now abandoned and is also a continuation-in-part of application Serial No. 666,206 filed June 17, 1957, for Phosphinoborine Compounds and Their Preparation and now abandoned.

Where the symbols R and Y are used in the claims which follow, it is to be understood that the groups for which each R stands in a single unit or formula may be the same or different, and the units for which each Y stands in each unit or formula may be the same or different also.

1. A process for preparing a B-halogenated phosphinoborine comprising: reacting with a halogenating agent selected from the class consisting of free halogens, hydrogen halides, and reactive halogenated hydrocarbons in which the halogen is bonded to a saturated carbon atom a phosphinoborine selected from the class consisting of phosphinoborines having the general formula [R PBH and phosphinoborines having the formula wherein each R is a hydrocarbon radical and n is an integer having the value of at least 3 indicative of the degree of polymerization.

2. The process of claim 1 wherein the phosphinoborine reacted has the general formula [R PBH where each R is as defined in claim 1.

3. A process for preparing a B-halogenated phosphinoborine comprising: reacting with a reactive halogenated hydrocarbon in which the halogen is bonded to a saturated carbon atom a phosphinoborine selected from the class consisting of phosphinoborines having the general formula [R PBH and phosphinoborines having the general formula [R PBH LJRPBHJ wherein each R is a hydrocarbon radical and wherein n is an integer having the value of at least 3 indicative of the degree of polymerization.

4. The process of claim 3 wherein the phosphinoborine is dimethylphosphinoborine trimer and the halogenated hydrocarbon is CCl.;.

5. The process of claim 3 wherein the phosphinoborine is the dimethylphosphinoborine methylphosphinoborine copolymer and the halogenated hydrocarbon is CCl.;.

6. The process of claim 3 wherein the phosphinoborine is methylethylphosphinoborine trimer and the halogenated hydrocarbon is CCl 7. The process of claim 3 wherein the phosphinoborine is dimethylphosphinoborine tetramer and the halogenated hydrocarbon is CHCI 8. The process of claim 3 wherein the reaction is carried out in the presence of an aluminum trihalide catalyst.

9. The process of claim 8 wherein the phosphinoborine is dimethylphosphinoborine trimer, the halogenated hydrocarbon is CCl and the catalyst is AlCl 10. The process of claim 8 wherein the phosphinoborine is dimethylphosphinoborine tetramer, the halogenated hydrocarbon is CH Cl and the catalyst is AlCl 11. The process of claim 8 wherein the phosphinoborine is dimethylphosphinoborine trimer, the halogenated hydrocarbon is CH I and the aluminum trihalide is A11 12. The process of claim 8 wherein the phosphinoborine is dimethylphosphinoborine trimer, the halogenated hydrocarbon is CH Br and the aluminum trihalide is AlBr 13. The process of claim 8 wherein the phosphinoborine is dimethylphosphinoborine trimer, the halogenated hydrocarbon is CH C1 and the aluminum trihalide is AlCl 14. The process of claim 8 wherein the phosphinoborine is dimethylphosphinoborine trimer, the halogenated hydrocarbon is CH B1' and the aluminum trihalide is AlC1 15. The process of claim 8 wherein the phosphinoborine is dimethylphosphinoborine linear polymer, the halogenated hydrocarbon is CH Cl and the aluminum trihalide is AlCl 16. The process of claim 8 wherein the phosphinoborine is dimethylphosphinoborine trimer, the halogenated hydrocarbon is C H Cl and the aluminum trihalide is AlCl 17. A process for preparing a B-halogenated phosphinoborine comprising: reacting with a free halogen a phosphinoborine of the general formula [R2PBH21 wherein each R is a hydrocarbon radical and n is an integer having the value of at least 3 indicative of the degree of polymerization.

18. The process of claim 17 wherein the phosphinoborine is dimethylphosphinoborine trimer and the free halogen is bromine.

19. The process of claim 17 wherein the phosphinoborine is dimethylphosphinoborine trimer and the free halogen is bromine, the dimethylphosphinoborine being added in the form of a methylene bromide solution.

20. The process of claim 17 wherein the phosphinoborine is dimethylphosphinoborine trimer and the free halogen is bromine, the free halogen being added in the form of an acetic acid solution.

21. A process for preparing a B-halogenated phosphinoborine comprising: reacting with a hydrohalogen acid a phosphinoborine having the formula [R lE'BI-I wherein each R is a hydrocarbon radical and n is an integer having the value of at least 3 indicative of the degree of polymerization.

22. The process of claim 21 wherein the phosphinoborine is dimethylphosphinoborine trimer and the hydrohalogen acid is HF.

23. The process of claim 21 wherein the phosphinoborine is dimethylphosphinoborine trimer and the hydrohalogen acid is HCl.

24. A phosphinoborine polymer of ring configuration composed of between 3 and 4 phosphinoborine units, each of said units having a formula selected from the group consisting of [R PBY and [OHACHQm 3 2] wherein each R is selected from the group consisting of alkyl, lower alkenyl, lower cycloalkyl, phenyl and lower alkyl-substituted phenyl, wherein each Y is selected from the class consisting of hydrogen and halogen, at least one of said Y symbols of at least one of the said units representing one of said halogens, and wherein m is an integer of between 3 and 6.

25. A phosphinoborine polymer having a ring configuration and composed of between 3 and 4 monomeric phosphinoborine units, said polymer having the formula [R PBY wherein each R is selected from the class consisting of alkyl, lower alkenyl, lower cycloalkyl, phenyl and lower alkyl-substituted phenyl, wherein each of the Y symbols is selected from the class consisting of hydrogen and halogen, at least one of said Y symbols of at least one of the said units representing one of said halogens, and wherin n is an integer of between 3 and 4.

26. A phosphinoborine polymer having a bicyclic ring configuration and the general formula [R PBY [RPBY] wherein each R is selected from the class consisting of alkyl, lower alkenyl, lower cycloalkyl, phenyl and lower alkyl-substituted phenyl and each Y is selected from the class consisting of hydrogen and halogen, at least one of said Y symbols representing one of said halogens.

27. A phosphinoborine polymer having a ring configuration and composed of between 3 and 4 monomeric phosphinoborine units, said polymer having the formula wherein each Y is selected from the class consisting of hydrogen and halogen, at least one said Y symbols repreresenting one of said halogens and where m is an integer of from 3 to 6 and where n is an integer of between 3 and 4.

28. A phosphinoborine polymer having a ring configuration and the general formula [(CH PBX where each X is halogen and n is an integer of between 3 and 4.

29. A phosphinoborine polymer having a ring configuration and the general formula [(CH PBCl 30. A phosphinoborine polymer having a ring configuration and the general formula [(CH PBCl 31. A phosphinoborine polymer having a ring configuration and the formula [(CH PBCl [Cl-I PBH].

32. A phosphinoborine polymer having a ring configuration and the formula [(CH PBI 33. A phosphinoborine polymer having a ring configuration and the formula [(CH PBBr 34. A phosphinoborine polymer having a ring configuration and the formula [(CH PBF 35. A phosphinoborine polymer having a ring configuration and the formula [CH (C H )PBCl 36. A phosphinoborine polymer having a ration and the general formula [R PBX X is halogen, n is an integer of between each R is lower alkyl.

37. A phosphinoborine polymer having a linear configuration and formed of a plurality of monomers of the general formula [R PBY joined to one another through tetracoordinate boron-to-phosphorus bonding, between about 4 and 1000 of said monomers constituting said chain, wherein each R is selected from the class consisting of alkyl, lower alkenyl, lower cycloalkyl, phenyl and lower alkyl-substituted phenyl and each Y is selected from the class consisting of hydrogen and halogen, at least one of said Y symbols representing one of said halogens.

38. The linear phosphinoborine of claim 37 wherein each R is methyl and each Y is chloro.

ring configuwherein each 3 and 4 and References Cited in the file of this patent Wagner et al.: Abstract of Papers, ACS Meeting, pages 49-0 to 50-0. 

24. A PHOSPHINOBORINE POLYMER OF RING CONFIGURATION COMPOSED OF BETWEEN 3 AND 4 PHOSPHINOBORINE UNITS, EACH OF SAID UNITS HAVING A FORMULA SELECTED FROM THE GROUP CONSISTING OF (R2PBY2) AND 